Stimulant users are at risk for AIDS due to the use of intravenous methods of drug administration and hypersexual, unsafe sexual practices. The development of a clinically viable treatment approach would reduce HIV transmission by reducing the frequency of high risk behavior associated with stimulant use. One currently promising outpatient treatment approach, the neurobehavioral model, is limited by significant dropout rates due to unacceptably high levels of stimulant withdrawal symptomatology. Research with cocaine users suggests that 2 medications hold the most promise in reducing this stimulant withdrawal symptomatology, desipramine and bromocriptine. The research proposed in this application includes a placebo-controlled, double-blind comparison of desipramine vs. bromocriptine as adjunctive medications in the treatment of cocaine and methamphetamine dependence. Subjects in the study will be 150 cocaine users and 150 methamphetamine users who will be randomly assigned to receive desipramine, bromocriptine, or placebo in a double-blind manner. The pharmacotherapy evaluation will be completed while all 300 subjects are concurrently receiving the structure, support and counseling provided by the neurobehavioral treatment procedures. Expected results should address the following issues: 1. Does treatment for stimulant abuse reduce high risk behavior for transmission of HIV? 2. Is bromocriptine or desipramine useful in reducing stimulant withdrawal syndromes from amphetamine or cocaine use? 3. Do either of these drugs promote retention in treatment? 4. Is the neurobehavioral treatment approach differentially effective with cocaine vs. amphetamine users? 5. Are there pre-treatment factors which are predictive of in-treatment performance? 6. Are there pre-treatment factors or in-treatment measures which are predictive of drug use status at follow-up? 7. Are there identifiable antecedents to stimulant relapse? It is anticipated that the information obtained from the research proposed in this application will improve treatment options for stimulant users, and consequently reduce behaviors associated with the transmission of HIV.